craftgrrl | Iron on images are not the size I want them to be after scanning.

I havthese bug stickers an flower stickers I scanned and am trying to put onto iron on paper, for the quilt I am doing for a friend, but they're coming out much darker than I want them to, and quick fix on my editing software's not fixing it. Plus the images are not true to size once scanned. I scanned the pictures 10 at a time or so cause I wanted to be able to get a bunch on one sheet but it's seemingly not working to well. is there any way I can scan them one by one on the scanner then paste them into a printing program or something so I can print a bunch on one sheet of paper, but scan only 1 at a time.

Also on the iron on paper there's very fine white lines running through my image that were not there in the test print on plain paper, why would that be?

And finally, yes I have a picture to show you all with the question, and it's not just a text only post:)